Control for the conventional voice coil motor in an optical disk drive is referenced with current limit information of the voice coil motor and the optical disk drive designer can assign gain value in accordance with an ideal object value with which the voice coil motor can operate safely so as to apply for designing the controller directly. The voice coil motor of this type of optical disk drive is apt to create over current and results in being burned out due to related factors such as signal correction difference, controller design difference, optical disk drive worn-out difference, environment difference and component damage because of not complying a hazard value of component signal restriction and due to the voice coil motor being abrasive wear after being used a long period of time by the user. Hence, the optical disk drive is unable to work normally.